I recently had an email from a colleague asking me what I would do if I was examining a thesis and the vast majority of the literatures were over ten years old. Would this be a problem? What would I say?

Well I agreed that this was nearly always a problem in science, where knowledge-building is usually taken to be iterative – researchers build on what has gone before. But using dated literatures was also likely to be a problem in the social sciences, arts and humanities. However, I said, I often saw another problem in these disciplines – theses which had the exact opposite difficulty – there was nothing in the literatures that was presented that was over ten years old. It was all ‘new’. This could be equally worrying, I suggested.

Age-related literature problems arise for examiners because having either too much ‘vintage’ OR too much ‘just off the press’ means that the writer is not achieving what literatures work is intended to do – namely :

(1) the thesis writer must locate their work in the field

With a tiny handful of exceptions, most fields of study are more than ten years old. And even if they have just been invented, they usually draw on other fields which are well established. Examiners expect doctoral researchers to show that they understand something of the development of their field, and that they understand why it is the way that it is. In other words, the researcher must show how the field they are in, as well as the problem that they are researching, are historically situated. They must indicate what seminal texts and writers are relevant. They must also indicate ongoing debates in the field.

An examiner may well conclude that a researcher who works with literatures that are all very recent is someone who has, either knowingly or not, adopted a kind of amnesiac stance to what they are doing.

(2) the thesis writer must situate the contribution that they are going to make

There are very few fields in which there has been no scholarly activity for a long time. Scholars generally live in crowded territories where someone is always writing something that is relevant to at least part of their endeavour. So reviewing the literatures doesn’t just mean coming to terms with history. It means getting to grips with the present. In order to specify the contribution to be made, the researcher must survey the field and its trends – and this means right up to the moment. Presenting a set of texts that are over ten years old will appear to examiners as an ossified view, stuck in a particular period.

Of course with a thesis, as with a book or an article, there does come a point when the researcher just has to stop reading and finish the piece off. There’s no doubt that it is absolutely infuriating for journal article writers to send something off for review and have it wait for months to be looked at and then be told by a referee that they haven’t referred to something that came out in the last two weeks. But this doesn’t matter so much with a thesis, as it’s possible to add a postscript or footnote about something new and crucial right up until the last few days. And it’s also possible to have a conversation during the viva about why there isn’t a reference to something very recent, because of the necessity of a cut-off point. There really is not much excuse* for not having read at least a decent number of texts that have been around for the last few months and a few years.

(3) the thesis writer must indicate what they are using from the field as a building block for their work.

Very few researchers start from scratch. They always use some ideas and approaches that have gone before. This is not a problem, it’s the way that knowledge is constructed. So one of the major tasks of the literature review is for the researcher to identify the ideas and approaches that they will use. If there is no recent literature referred to in the review, then the examiner is likely to read this as the researcher not knowing the field, and therefore not building on its most recent developments.

Now I can imagine a piece of research where the researcher wants to go back to something that happened in the field some time before. They think there is something in a piece of work done quite some time ago that could be important to the work that they want to do. In this case, the literature that is being used to develop their piece of research will be older. However, in order to make the case that this is needed, the thesis writer still needs to deal with more recent work, indicating why and where it is inadequate, and what the significance of the older literatures might be.

BUT THERE IS NO FORMULA OR RECIPE TO HELP.

Clearly there is no hard and fast rule about how much ‘old’ and ‘new’ literatures must be used a literature review. It depends on the field and the topic. It’s another case of what Barbara and I call the Goldilocks rule – not too much, not too little. Getting the balance right can be tricky for researchers, but not at the extremes and probably not in this case. Too much ‘old’ literature and the examiners worry, too much ‘new’ and they worry just as much!

(* The exception here is in situations when researchers literally cannot access recent texts. This is the case in some parts of the world and it is why open access is so important.)

8 Responses to the literature review – how old are the sources?

we should use either the Lens Directed Approach or the Conceptual Matrix Mapping Approach to stream line Literature review. I too am facing the problem of dealing with different sources of literature and research materials which have either become outdated or are not directly related to my field.
Good to read this write up.

Hi, really interesting post, thank you as always. I’ve been facing similar issues over the last few weeks when writing my own thesis intro/lit review. It is really useful to hear the opinion on literature age from an examiners stand-point. I’ve written up a few thoughts on my own thesis writing here – http://abovetheleadingedge.wordpress.com/ and hoping to write up something about the intro soon. Thanks again for a really useful post.

As ever, thoughtful, interesting, informative and constructive. I was particularly struck by your comment on reviews that consider nothing older than the last few years. Mind, not all disciplines are agreed on a relatively limited number of ‘big questions’ that remain central to the research agenda over time. Educational research, for example, tends to be more ‘of the moment’, often responding to particularly pressing issues of policy or practice.

The other thing that has struck me is that some doctoral programmes formally require a written review of the literature at quite an early stage. This is the case in most professional doctorates. And I’ve noticed that when examining theses based on professional doctorates, the thesis is often grounded in the literature review that was submitted some years before. Perhaps those who supervise or lead professional doctorates should encourage their students to remember that the thesis should include relevant literature whether or not it was considered in the initial literature review?

Thanks so much for this post. This is an issue I’ve found challenging and while my supervisor once mentioned ‘ mind the years of your literature’ … I found her statement really vague. Indeed, I’ve struggled to find the balance between how much of the new and old will be acceptable for my thesis. Your post has been very helpful. Hope I get the balance right.